Racial and ethnic minorities continue to be disproportionately affected by the HIV epidemic. Latinos, including Puerto Ricans, comprise 14% of the population but accounted for 18% on new diagnoses in 2006. In turn, Puerto Rico is one of the most affected areas among the US territories with more than 32,000 reported cases. HIV heterosexual transmission continues to grow exponentially among Puerto Ricans encompassing more than 40% of all reported cases. Heterosexual serodiscordant couples (HDC) need urgent attention in order to prevent the infection of the negative partner and promote adherence to highly active antiretroviral therapy of the infected partner. Focusing on HDC is an innovative way of tackling both issues. Still, most studies and prevention efforts with Puerto Ricans continue to concentrate on the individual ignoring couple dynamics. Therefore, the proposed study has three aims: (1) Explore variables related to relationship experiences among Puerto Rican heterosexual serodiscordant couples. (2) Explore the perceived influence of these variables on safe sexual practices among couples and adherence to treatment of the person living with HIV/AIDS, from the perspective of both members of the dyad. (3) Identify issues that would need to be integrated into a couple-oriented intervention aiming to promote safer sexual practices in the dyad and adherence to treatment of the PLWHA. In order to achieve aims 1 and 2 we will carry out qualitative interviews with 20 HDC (n=40). The couples will be balanced with regards to the HIV infected partner (male or female) to explore gender variations in the results. We will first interview participants individually, and afterwards conduct a joint interview (60 interviews in total). We will explore relationship experiences through the following constructs that emerge from our literature review: (1) HIV status disclosure process;(2) couple's communication;(3) sexual intimacy;(4) social support;(5) domestic violence;(6) HIV/AIDS stigmatization;and (7) other individual and couple related issues that may arise from the qualitative work. Throughout the interviews we will also discuss patterns of adherence to treatment, safer sexual practices, and their perceived relation to experiences within the dyad. In order to achieve aim 3 we will carry out four focus groups (N=40) with men and women in HDC to identify issues needed to develop interventions targeting Puerto Rican serodiscordant couples. We will carry out groups divided by gender (male and female) and by HIV status (seropositive and seronegative). We have been unable to find published studies with Puerto Rican HDC that explore how relationship experiences with the primary partner may influence the person living with HIV/AIDS'desire and capacity to adhere to treatment, and the practice of safer sex. These concerns drive this research proposal. PUBLIC HEALTH RELEVANCE: This study seeks to understand how Puerto Rican heterosexual serodiscordant couples face the challenges of adherence to treatment and safe sex within the relationship dyad. Considering the growing amount of reported cases of heterosexual transmission in Puerto Rico, this effort can serve as the foundation for future studies that aim to develop and test interventions geared towards serodiscordant couples. This can better the lives of PLWHA, help avoid new infections within the serodiscordant couple dyad, and therefore have a positive impact on public health.